Indian troops take up positions on rooftops around the Golden Temple during operation Blue StarPhoto: GETTY IMAGES

Sikh leaders have accused Britain of "back-stabbing" and attacking their faith after official documents revealed that an SAS officer had advised India on its plans for a military assault on Sikh militants inside Amritsar's revered Golden Temple.

Indian troops attacked the temple, Sikhism's holiest place of worship, in June 1984 killing 492 militants, pilgrims and soldiers. The operation, termed Blue Star, plunged the country into some of the worst communal violence in its history. Sikh activists claim thousands died in the operation.

Indira Gandhi, the Indian prime minister at the time who sought British advice and ordered the raid, was assassinated in revenge by her Sikh bodyguards in October that year, provoking a wave of anti Sikh riots in which 8,000 were killed including 3,000 Sikhs in Delhi.

An Indian Sikh devotee takes a dip in the holy sarover (water tank ) at the Golden Temple

David Cameron, the prime minister, has ordered an inquiry into the claims after MP Tom Watson said they were based on letters declassified under the 30 year rule. A spokesman said the raid had led to a "tragic loss of life" and that the claims had raised "very legitimate concerns."

The Cabinet Secretary had been asked to urgently establish the facts but neither the prime minister nor the foreign secretary had been aware of the papers until their release this week.

Mr Watson, whose West Bromich East constituency has a large Sikh population, cited two letters marked 'Top Secret and Personal', which conveyed Margaret Thatcher's consent for a British officer to advise the Indian government on evicting Sikh militants from the Golden Temple and the need to keep Britain's involvement from the public.

One of the letters, from the Foreign Secretary's Principal Private Secretary Brian Fall to his opposite number in the Home Office, advised him the SAS advice had been accepted by Mrs Gandhi and the operation was likely to be launched shortly. The letter, dated February 23rd, warned of repercussions from Sikhs in Britain.

Indian troops attacked the temple, Sikhism's holiest place of worship, in June 1984 killing 492 militants, pilgrims and soldiers (REX FEATURES)

"The operation could, in the first instance, exacerbate the communal violence in the Punjab. It might also, therefore, increase tension in the Indian community here, particularly if knowledge of the SAS involvement were to become public," he wrote to the Home Secretary's private secretary Hugh Taylor.

Their concerns about communal violence were borne-out in the riots and massacres which followed, but the involvement of the SAS in preparing the controversial raid remained a secret until Mr Watson's disclosures this week.

The Dal Khalsa, one of the original militant groups which continues to support the creation of a Sikh state, Khalistan, said Sikhs were shocked by the revelation.

"The UK government collaborating with the Indian government to plan the attack has shattered the Sikhs from within. The Sikhs are deeply hurt and the news has left them numbed," said spokesman Kanwar Pal Singh.

"The report has exposed that the attack was not spontaneous. They had been planning it for months… thousands of Sikhs live in UK and are grateful to the country for providing them opportunity to equal growth but the role of the then UK government amounts to back-stabbing," he told the Telegraph.

Jathedar Avtar Singh, President of the Shiromani Gurdwara Parbandhak Committee which manages the Golden Temple, welcomed David Cameron's announcement of an inquiry but condemned Britain's involvement.

"We strongly condemn the role of UK government in the attack on holiest site of Sikhs. We treat it as an attack on the Sikh religion," he said.

This morning it has been learned that the British Government played a part in the attack in 1984 on the Golden Temple. It was brought to our attention by Dr Kamalroop Singh on his facebook page.

Newly released records at the National Archives, London shows that the British Government was involved in the planning and military assault on the Golden Temple, the most important shrine of the Sikhs. Their role extended to sending SAS, or secret forces to aid and coordinate the attack.

Tom Watson, UK MP for West Bromwich East, shared his concerns about the information contained in the documents and has stated that he, 'is writing to the Foreign Secretary about this matter and will raise it in the House of Commons,' expecting a full explanation. He also been on BBC Radio this morning to discuss these alarming documents, he further stated, 'the documents have only just been released after 30 years' and he's shocked by what he's seen.

Pod cast of Interview with Tom Watson on BBC Asian Network

The LetterThe letter from the National Archives was first mentioned this morning on the Stop Deportations blog the states the following:

"The Indian authorities recently sought British advice over a plan to remove Sikh extremists from the Golden Temple in Amritsar. The Foreign Secretary decided to respond favourably to the Indian request and, with the Prime Minister's agreement, an SAD [sic] officer has visited India and drawn up a plan which has been approved by Mrs Gandhi. The Foreign Secretary believes that the Indian Government may put the plan into operation shortly".

The serving Prime Minister at the time was Margaret Thatcher who is now deceased, the thirty year rule ensures that many individuals who have undertook their policies can not be held to account. However as as Sikhs commemorate their role in the centenary of World War, answers will be needed and a full enquiry to be held. The petitionAs a result of this mornings news there has been further comment from MP Paul Uppal who has set up a petition to 'launch an urgent inquiry into British involvement into the 1984 attack on Amritsar.' This can be accessed on the following link